Related Experiment Videos
Early development of human Merkel cells.
1Department of Dermatology, Mannheim Medical School, University of Heidelberg, Germany.
Experimental Dermatology
|November 1, 1992
Summary
Human fetal Merkel cells, crucial skin sensory receptors, develop earlier than previously believed. These cells appear by fetal week 8, coinciding with epidermal development, suggesting an earlier origin.
Area of Science:
- Dermatology
- Developmental Biology
- Cell Biology
Background:
- Human fetal Merkel cells are recognized as epidermal derivatives.
- Previous research identified these cells in the epidermis by fetal weeks 10-12 using cytokeratin (CK) 8 and 18 antibodies.
- The precise timing of early Merkel cell development within the human epidermis remained unclear.
Purpose of the Study:
- To investigate the earliest appearance and developmental timeline of human fetal Merkel cells.
- To analyze Merkel cell presence and morphology during early human embryonic and fetal development (weeks 7-9).
Main Methods:
- Utilized immunofluorescence and immunoperoxidase microscopy techniques.
- Employed antibodies against cytokeratin (CK) 20, a marker specifically expressed in Merkel cells.
- Analyzed human embryonic and fetal skin samples from gestational weeks 7 to 9.
Main Results:
- Identified the first human fetal Merkel cells as early as gestational week 8.
- Observed Merkel cell development concurrently with the formation of the epidermis's third layer (expressing CKs 1, 10, 11).
- Noted that at week 8, Merkel cells were primarily suprabasal, with round-to-oval shapes and infrequent short dendrites; their numbers increased significantly by week 9.
Conclusions:
- Provide evidence for a significantly earlier development of human fetal Merkel cells within the epidermis than previously established.
- Suggest that Merkel cells may differentiate from embryonic basal keratinocytes.
- Highlight the utility of CK 20 as a specific marker for identifying early Merkel cell development.